A number of extemporaneous products, meaning products consisting of the solution or mixture of at least two different substances, of which, for instance, one in liquid state and the other in powder state, which are kept separate from each other until they are used, are known in the medicinal sector, the pharmaceutical sector and the cosmetic sector.
For such extemporaneous products, packagings are known essentially consisting of a container closed on the bottom and which extends at the top into a neck, at the top of which a mouth is defined; inside the container, a first substance is contained, generally in liquid state.
In the mouth of the container, a receptacle is housed of a second substance consisting of a hollow cylinder-shaped body, closed at the bottom by a breakable bottom and open at the top; the bottom of the receptacle, as long as this remains intact, separates the second substance from the first.
Inside the receptacle, a cutting element is sealed consisting of a tubular body, the bottom end of which is sectioned according to an oblique plane or shaped like the beak of a flute, the upper end of which extends beyond the upper end of the receptacle. The cutting element slides axially compared to the receptacle between a non-interference configuration, in which it is placed above the intact bottom of the receptacle, and a cutting configuration, in which, pushed towards the bottom of the receptacle, it cuts this along the surrounding edge thereby placing the thus-opened receptacle in communication with the container.
The known packagings also feature a cover cap associated with the container neck by means of a threaded coupling; the lower edge of the cap is temporarily fastened, along a breakage line, to a seal ring fastened to the container neck and featuring a weakened axial line at which point it opens.
Finally, inside the cap, a ring-shaped raised part is defined which, after the cap has been screwed onto the neck of the container, is coupled with the top edge of the receptacle, which is elastically deformable in centripetal direction, to form with this a single body.
When the time comes to use the product, the cap is screwed onto the neck of the container thereby breaking the ring seal which detaches and opens. The screwing up of the cap causes the sliding of the cutting element inside the receptacle until the bottom of this is cut; the second substance thus pours from the receptacle into the container inside which it mixes with the former substance, forming the product. To dispense the product thus formed, the cap simply has to be unscrewed to extract, together with the cap, also the receptacle and the cutting element opening the container dispenser mouth.
These known type packagings are not free of drawbacks, including the fact that, while keeping the two components making up the product separate until preparation of the latter, they do not permit isolating the one from the other.
More specifically, the vapours released by the liquid substance in the container partially permeate the inside of the receptacle where a powdery substance, often hygroscopic, is generally present.
Before product preparation, while the two substance are still separate, the powdery substance absorbs the vapours released by the liquid substance, becoming impregnated and thickening into agglomerates. When the time comes to prepare the product and the receptacle is opened and placed in communication with the container, the agglomerates that have formed tend to remain inside the receptacle and, even when they have shifted into the container, find it hard to dissolve and disperse completely in the liquid substance.
The composition of the thus-formed product does not correspond to that provided; in the event of the product being a pharmaceutical or medicinal product, this causes an indeterminable alteration of the contents of its active ingredients, as well as of the established dosage and, therefore, a disadvantageous modification of the therapy studied for a patient.
This problem is worsened by the fact that the receptacles of known packagings are generally made of polymer materials featuring a certain degree of permeability to vapours. The permeability to vapours is further accentuated at the bottom of the receptacle which, being breakable, is normally of low thickness and/or attached to the body of the receptacle along lines of extra-weak thickness.